Split brains, gut bacteria: Hello all. Time for another strange, interesting, mind boggling (and slightly scary!) blog post. This one is all about the future of technology and how it might possibly be integrated with humans and… our brains!
In Physics there are many topics which are a little strange and do not seem to match how we experience the world normally.
Inspiration for this post came from:
- Yuval Noah Harari and his trilogy of books about us humans (Sapiens, Homo Deus and 21 Lessons for the 21st Century)
- The Borg from Star Trek
- A video explaining the experiments on ‘Split Brain’ patients by CGP Grey.
Split Brain patients??
It turns out that our brains are made out of 2 parts, the left hemisphere and the right hemisphere. The left controls the right part of the body and receives information from the right and vice versa with the right hemisphere. Crucially, the left hemisphere controls pretty much all of verbal communication. The right hemisphere does not contribute to what we say, but it does hear, using the right ear. Normally these two hemispheres are connected and are in constant communication with one another, but…
Treatments for epilepsy were conducted in the past in which the two hemispheres were disconnected which helped to reduce seizures by keeping the disruption within one hemisphere. The experiment worked brilliantly, except that the patients of these treatments experienced some strange side effects. At times it seemed that the left arm seemed to have a mind of its own. It would choose a different item of clothing, or a different type of food from the fridge than what the patient intended. After careful experimentation it seemed that the patient’s personality had been split into two. One ‘person’ existed in the right hemisphere and the other in the left. Scientists conducted experiments with volunteers to conclude this, which can be seen in the video I linked to above.
Are we so different from split brain patients?
It would seem then, that we therefore are already two people in our heads, but in direct and constant communication with each other so much so, that we feel like one person. In groups of people, this phenomenon is also observed. A group of people will seem to have one personality, when viewed in a general way by looking at the behaviour of the group. A similar thought experiment could take place with hives of bees, which have ‘hive intelligence’ or armies of ants. In a similar way, humans working on huge projects, such as building a rocket and landing it on the moon are very very unaware of how their individual jobs connect with the overall aim and as such the overall personality and intelligence of the group is different to that of an individual within the group.
This is me, that is not me!
We all have an idea of stuff is us and what stuff is not us. My head is me, my glasses are not me. My skin is me, my red blood cells is me, the food is not me… But, it will become me at some point. At what point does the food you eat become you? When it enters your mouth? Or when the nutrients go into your bloodstream? When the nutrients make it to your cells? What about the bacteria living in your digestive system? They have entirely different DNA, so cannot possibly be you, right? Did you know that they affect how your brain works, even down to your very personality? If you had different gut bacteria, your personality would be different, so would that mean that ‘you’ are different?
Stop! My brain hurts!
This is starting to get a bit weird, right? We think we know what we are and what is not us, but when we breathe, the oxygen in the air becomes us and bits of us become carbon dioxide which makes up the air. Plants then take that in during photosynthesis and in no time at all it is now part of the plant.
We may eat some plants, and/or animals which ate some plants and they then become part of us. Meanwhile, the bacteria living inside of us are affecting our behaviour and personality. In fact, the mitochondria that live inside of all of our cells in our body used to be classified as an entirely separate organism, but at some point in our evolutionary history it invaded a cell and since then they have existed together. And now it turns out you can even chop a brain in half and you get two people living inside one human!
Ok. This is too much for now! Next post I shall build on this idea and suggest what is in store for us in the distant future as we start to combine with technology!
A bit about the author, Paul H:
Paul is a qualified and experienced Physics, Maths, and Science teacher, now working as a full-time tutor, providing online tuition using a variety of hi-tech resources to provide engaging and interesting lessons. He covers Physics, Chemistry, Biology, and Science from Prep and Key Stage 3 through to GCSE and IGCSE. He also teaches Physics, Maths, and Chemistry to A-Level across all the major Exam Boards.